Exterior housing for a shower drain pump



FIG. 1 is a perspective view of an exterior housing for a shower drain pump showing our new design;

FIG. 2 is left side elevational view, the right side view being a mirror image;

FIG. 3 is a front elevational view; and,

FIG. 4 is a bottom plan view.

The broken line representations are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for an exterior housing for a shower drain pump, as shown and described. 